1. Field of the Invention
The present invention relates to an image processing device that extracts a group of digest images from a plurality of time-series images that are taken at different points of time and arranged in chronological order, a computer readable storage medium that stores therein an image processing program, and an image processing method.
2. Description of the Related Art
A technology is known that extracts helpful images, e.g., images indicative of positions of scene changes, from time-series images, such as video images or a series of still images, as a group of digest images. A user can quickly grasp the outline of the time-series images just by scanning the extracted group of the digest images without scanning all the time-series images and, moreover, select desired scenes or images in a simple manner.
A typical, well-known manner of extracting a group of digest images involves calculating the amount of change between adjacent images and then extracting an image having a large amount of change on the basis of the calculated amount of change. For example, Japanese Patent Application Laid-open No. 2006-41797 discloses a technology that compares the amount of change between adjacent images (adjacent frames) with a predetermined threshold and extracts an image at a changing point where adjacent frames show a change that is greater than or equal to the threshold.